The present invention concerns a fitting permitting the connection a water reservoir and a porous enclosure comprising a ceramic cone which allows water to pass slowly therethrough to continuously and individually supply water to plants, in proximity of their roots, and in predetermined volume, and especially to potted plants. The fitting of the invention is provided with a plurality of different threads to be adaptable to most commercially available plastic bottles, which bottles are utilized as water reservoirs.
The fitting of the invention allows a fully reliable interconnection between the bottle and the porous cone. This feature is essential in view of the fact that the purpose of the device is to maintain plants alive in case of absence, e.g. without surveillance, particularly in rooms (apartments) where flooding must be avoided.
A plurality of devices are known attempting to provide the same result, but these known devices have inconveniences prohibiting their commercial exploitation.
French patent No. 2673356 concerns a cap whose truncated form permits to adapt it to different neck dimensions of bottles on which it is to be installed.
The disadvantages of this device are as follows:                the engagement between the cone and the neck of the bottle is provided along a single line about the cone and in the interior of the neck, which is insufficient to obtain a safe interconnection of these two parts,        to obtain tightness, the truncated part must be made of medium-soft plastic material, which, once more, does not permit a safe interconnection between the cone and the bottle.        
Consequently, if the bottle is full, it may be driven under the impact of its weight and may become disengaged from the cap. The water can accordingly flow out instantaneously from the bottle causing flooding, thereby making the device inappropriate for use in apartments, and in all cases in which the user relies on the water supply to maintain his plants alive.
Swiss patent No. 391368 concerns another example in which water is contained in a hollow body whose pointed base is forced into the soil. The hollow body serving as reservoir and the portion driven into the soil forming one single unitary non- separable assembly so that it is not intended to use commercially available plastic bottles, thereby making the device cumbersome when it has to be stored.
The U.S. Pat. No. 4,300,309 describes a similar system having the same disadvantages.
The French patent No. 2252806 discloses a similar system with the same inconveniences and in addition, wicks must contribute to the water distribution, thereby making its use less practical as digging is necessary to embed the wicks into the soil, this device being thus designed to remain in the plant pot, which is contrary to the goal looked after which is to provide the device whose use is occasional.
The U.S. Pat. No. 6,128,856 describes an irrigation device comprising a cap having a rotary valve connected on one side to a tube fixed to a dispensing device and on the other side to a bottle adapted to be threaded thereinto. The inconveniences of this known device are                its complexity, thus its cost;        the difficulty to provide a suitable control,        the lack of reliability for a device that can become soil contaminated,        the need for servicing to maintain performances,        a single type of bottle that can be threadably engaged therewith, obliging the user to retain the adapted bottle, thus to encumber himself.        
U.S. Pat. No. 5,896,700 describes an irrigation device comprising a water reservoir threaded on a device comprising a pointed member adapted to be driven into the soil to allow water to flow thereinto, a filter being interposed therebetween to control the flow. The disadvantage being once more the space occupation and the impossibility to use a large choice of commercially available plastic bottles.